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Iodine is an essential element for the synthesis of thyroid hormones. Therefore, a reliable marker of iodine supply is important. Iodine is predominantly excreted via kidneys, but also via salivary glands. Our aim was to introduce a new and simple method for determination of salivary iodine concentration (SLIC).

Water resources are vital for life, yet they are exposed to various risks. In the estern Rif of Morocco, the Oued Kert is a crucial water resource for a large population. Therefore, evaluating their health status is essential to ensure their optimal preservation. In this context, five stations (S1, S2, S3, S4, and S5) were monitored, during the four campaigns (September, December, March, and June 2022), to assess the physicochemical quality of water. In this sense, seven parameters were measured, temperature, pH, electrical conductivity (EC), Biochemical oxygen demand (BOD5), Chemical oxygen demand (COD), nitrates, and ammonium. In addition, an evaluation of metal contamination was conducted during a single campaign (May 2022) by measuring four elements (Al, Fe, Li, and Mn). The levels of electrical conductivity (greater than 3000 μS cm-1), and COD (greater than 40mg L-1 in S2, S3, and S4) indicate poor water quality, while, the average concentrations of ammonium classify these waters as of moderate quality. The results of metal contamination revealed the presence of iron (Fe) at a concentration of 1.9 mg L-1 in S5, classifying these waters as of moderate quality according to Moroccan water quality standards.

The measurement uncertainty (MU) in environmental analyses is usually considered as a combination of the additive contributions from sampling, sample preparation and analytical measurement (usually instrumental). The target MU for such studies is usually relatively high due to the natural sample heterogeneity and/or the complicated pretreatment procedure required. In the analytical practice, the contribution of the sample preparation to MU is rarely evaluated. Thus, it remains a hidden part of the one related to the analysis. However, the knowledge for the contribution of sample preparation might provide important information and further possibility for optimization of the entire analytical procedure and reduction of the expanded MU of the analytical result. From statistical point of view, the separation of uncertainty contributions from the different steps is, generally, not a trivial task. Selection of the proper statistical approach depends on the data structure and quality, variables distribution, etc. In the present study, three different statistical methods for evaluation of the uncertainty contribution of the sample preparation were applied, compared, and discussed. The considered approaches are based on, both, classical and robust analysis of variances (ANOVA) applied to data from instrumental analysis of marine algae and bee honey samples, undergoing microwave digestion. Some general recommendations on the statistical approach selection are revealed based on real experimental data set. [ABSTRACT FROM AUTHOR]

Enhancing the performance of electrolytes stands as one of the key challenges for moving toward practical applications of Mg batteries. Within this work, we investigate different synthesis procedures for the state-of-the-art MgAlhfip electrolyte. The results show that the purity and electrochemical performance of MgAlhfip electrolytes depend on whether they are synthesized from organometallic or inorganic reagents. Additionally, electrolyte properties vary depending on the electrolyte preparation method, either in situ electrolyte formation or salt isolation. To improve electrolyte performance, we explore two approaches: additional salt isolation steps and the use of a scavenging additive. Salt precipitation results in a modest improvement in the coulombic efficiency of Mg plating/stripping, while a scavenging additive significantly reduces overpotentials and enhances coulombic efficiency, especially in electrolytes synthesized from inorganic reagents. Finally, investigated syntheses are evaluated in terms of their practical applicability through procedure complexity and costs of used chemicals. Based on this, we propose a synthesis procedure that strikes a balance between the electrochemical performance of Mg electrolyte and its costs. [ABSTRACT FROM AUTHOR]

Mineral composition of Nigella S. seed variety having Moroccan origin, was determined. The methodology consisted in Inductively Coupled Plasma Optical Emission Spectrometry (ICP-OES) determination after microwave assisted digestion. The accuracy of the procedure was assured by recovery studies of Nigella seeds samples spiked at different concentration levels. The results revealed that potassium was a predominate element, followed by calcium and magnesium. According to the microelements Moroccan black cumin seeds were good source of iron, zinc and aluminum. A comparative study has indicated variations in mineral content among black cumin seeds with different geographical origin. [ABSTRACT FROM AUTHOR]

Pollution by heavy metals is one of the most serious issues in the world, and the principal sources are manufacturing, fertilizers, mining, pesticides, transport, and wastewater discharge. In this study, the presence of macroelements (Nitrogen (N) and Phosphorus (P)) and heavy metals (Chromium (Cr), Nickel (Ni), Cadmium (Cd), Iron (Fe), Zinc (Zn), Lead (Pb), Cooper (Cu), and Manganese (Mn)) in the green tide caused by the green seaweed Ulva lactuca from Marchica lagoon (NE-Morocco, Mediterranean) was evaluated. The mean values of P and N in the algae were 1773.33 mg·kg −1 and 44.4 g·kg −1, respectively. The heavy metals have mean values following this descending sequence: Fe > Mn > Zn > Cu > Ni > Pb > Cr > Cd. This finding has suggested that Ulva has the strongest affinity to Fe and Mn among the metals examined. Mn, Fe, and Pb recorded the highest bioconcentration factors (BCFs), which were 1687, 1656, and 1643, respectively. Regarding their contribution to the Recommended Dietary Allowance (RDA), Fe showed a contribution of 13.58% to the RDA, while that of Mn varied between 4.42 % and 28.42%. The health risk assessment did not indicate any hazard related to the ingestion of Ulva lactuca. Therefore, this study suggests that Ulva lactuca in the Nador lagoon has the potential to bioaccumulate heavy metals and mitigate eutrophication. [ABSTRACT FROM AUTHOR]

The aim of this study was to investigate 30 different types of Dalmatian wines as a potential source of fluoride. A fluoride ion selective electrode was used to measure the fluoride concentration in each sample. The direct potentiometric method and the standard addition method were evaluated, the latter being suggested as more accurate and precise. Measurements were performed in two buffers, acetate buffer and total ionic strength adjustment buffer (TISAB), to compare their influence on fluoride determination. The obtained results show that TISAB is a better choice than acetate buffer as a medium for fluoride determination. According to the proposed method, mass concentrations of fluoride of 0.19 and 0.18 mg/L were found in the studied red and white wines, with standard deviations of 0.04 and 0.03 mg/L, respectively. All determined fluorine levels in the tested wines were within the recommended limits and do not pose a risk to human health. No significant difference was found between the fluorine content in white and red wines, but there was a difference depending on the place of origin of the wine. The measured pH values for all the wines studied (except one sample) are very similar and show no significant correlation with the fluoride content. [ABSTRACT FROM AUTHOR]

In this study, Ag-MnxOy/C composite catalysts deposited on reduced graphene oxide (rGO) and, for the first time on N-doped graphene oxide (NGO), were prepared via a facile synthesis method. The influence of the carbon support material on the activity and stability of the oxygen reduction reaction (ORR) and on the tolerance to ethanol in alkaline medium was focused and investigated. The physicochemical properties of the Ag-MnxOy/C catalysts were analyzed by X-ray diffraction (XRD), scanning electron microscopy with energy dispersive X-ray spectroscopy (SEM-EDS), Brunauer–Emmett–Teller (BET) method, atomic absorption spectroscopy (AAS), inductively coupled plasma-mass spectrometry (ICP-MS), and thermogravimetric gas analysis (TGA). Electrochemical characterization was performed by rotating disk electrode (RDE) experiments. The results show that the active manganese species MnO2 was assembled as nanorods and nanospheres on rGO and NGO, respectively. Ag was assumed to be present as very small or amorphous particles. Similar redox processes for Ag-MnxOy/rGO and Ag-MnxOy/NGO were examined via cyclic voltammetry. The Ag-MnxOy/rGO resulted in a more negative diffusion limiting current density of −3.01 mA cm−2 compared to Ag-MnxOy/NGO. The onset potential of approximately 0.9 V vs. RHE and the favored 4-electron transfer pathway were independent of the support material. Ag-MnxOy/NGO exhibited a higher ORR stability, whereas Ag-MnxOy/rGO showed a better ethanol tolerance. [ABSTRACT FROM AUTHOR]